Purpose : For your players to mine some ore 
Difficulty : 1/10
What you need : A computer , a server source , a compiler , and some good worth of knowledge.
Step one : To get into the mining guild I would assume to add this 
Code:
} else if (objectID == 2113) { //Mining guild stairs
if (playerLevel[playerMining] >= 60) {
stairs = 3;
skillX = objectX;
skillY = objectY;
stairDistance = 1;
} else {
sendMessage("You need 60 mining to enter the mining guild.");
}
Add that near your other objectID codes.
Next part : ADDING MINING TO YOUR SERVER
Difficulty : 1/10
Purpose : To use the mining guild of course 
Step one search for :
add these cases above it
Code:
case 2091:
if(GoodDistance2(absX, absY, objectX, objectY, 3)) {
if(actionTimer == 0){
if(playerEquipment[playerWeapon] == 1265 || playerEquipment[playerWeapon] == 1267 || playerEquipment[playerWeapon] == 1269 || playerEquipment[playerWeapon] == 1271 || playerEquipment[playerWeapon] == 1273 || playerEquipment[playerWeapon] == 1275)
{
coppermine();
} else {
sendMessage("You need a pickaxe to do this!");
}
}
break;
}
case 2094:
if(GoodDistance2(absX, absY, objectX, objectY, 3)) {
if(actionTimer == 0){
if(playerEquipment[playerWeapon] == 1265 || playerEquipment[playerWeapon] == 1267 || playerEquipment[playerWeapon] == 1269 || playerEquipment[playerWeapon] == 1271 || playerEquipment[playerWeapon] == 1273 || playerEquipment[playerWeapon] == 1275)
{
tinmine();
} else {
sendMessage("You need a pickaxe to do this!");
}
}
break;
}
case 2092:
if(GoodDistance2(absX, absY, objectX, objectY, 3)) {
if(actionTimer == 0){
if(playerEquipment[playerWeapon] == 1265 || playerEquipment[playerWeapon] == 1267 || playerEquipment[playerWeapon] == 1269 || playerEquipment[playerWeapon] == 1271 || playerEquipment[playerWeapon] == 1273 || playerEquipment[playerWeapon] == 1275)
{
ironmine();
} else {
sendMessage("You need a pickaxe to do this!");
}
}
break;
}
case 2097:
if(GoodDistance2(absX, absY, objectX, objectY, 3)) {
if(actionTimer == 0){
if(playerEquipment[playerWeapon] == 1265 || playerEquipment[playerWeapon] == 1267 || playerEquipment[playerWeapon] == 1269 || playerEquipment[playerWeapon] == 1271 || playerEquipment[playerWeapon] == 1273 || playerEquipment[playerWeapon] == 1275)
{
coalmine();
} else {
sendMessage("You need a pickaxe to do this!");
}
}
break;
}
case 2102:
if(GoodDistance2(absX, absY, objectX, objectY, 3)) {
if(actionTimer == 0){
if(playerEquipment[playerWeapon] == 1265 || playerEquipment[playerWeapon] == 1267 || playerEquipment[playerWeapon] == 1269 || playerEquipment[playerWeapon] == 1271 || playerEquipment[playerWeapon] == 1273 || playerEquipment[playerWeapon] == 1275)
{
mithmine();
} else {
sendMessage("You need a pickaxe to do this!");
}
}
break;
}
case 2105:
if(GoodDistance2(absX, absY, objectX, objectY, 3)) {
if(actionTimer == 0){
if(playerEquipment[playerWeapon] == 1265 || playerEquipment[playerWeapon] == 1267 || playerEquipment[playerWeapon] == 1269 || playerEquipment[playerWeapon] == 1271 || playerEquipment[playerWeapon] == 1273 || playerEquipment[playerWeapon] == 1275)
{
addymine();
} else {
sendMessage("You need a pickaxe to do this!");
}
}
break;
}
case 2107:
if(GoodDistance2(absX, absY, objectX, objectY, 3)) {
if(actionTimer == 0){
if(playerEquipment[playerWeapon] == 1265 || playerEquipment[playerWeapon] == 1267 || playerEquipment[playerWeapon] == 1269 || playerEquipment[playerWeapon] == 1271 || playerEquipment[playerWeapon] == 1273 || playerEquipment[playerWeapon] == 1275)
{
runemine();
} else {
sendMessage("You need a pickaxe to do this!");
}
}
break;
}
Then add these voids , you should know where....
Code:
public void coppermine(){
sendMessage("You mine some copper ore!");
addItem(436, 1);
addSkillXP((25*playerLevel[14]), 14);
actionTimer = 40;
setAnimation(625);
updateRequired = true;
appearanceUpdateRequired = true;
}
public void tinmine(){
if(playerLevel[14] >= 10){
sendMessage("You mine some tin ore!");
addItem(438, 1);
addSkillXP((50*playerLevel[14]), 14);
actionTimer = 40;
setAnimation(625);
updateRequired = true;
appearanceUpdateRequired = true;
} else {
sendMessage("You need 10 mining!");
}
}
public void ironmine(){
if(playerLevel[14] >= 20){
sendMessage("You mine some iron ore!");
addItem(440, 1);
addSkillXP((75*playerLevel[14]), 14);
actionTimer = 40;
setAnimation(625);
updateRequired = true;
appearanceUpdateRequired = true;
} else {
sendMessage("You need 20 mining!");
}
}
public void coalmine(){
if(playerLevel[14] >= 35){
sendMessage("You mine some coal!");
addItem(453, 1);
addSkillXP((100*playerLevel[14]), 14);
actionTimer = 40;
setAnimation(625);
updateRequired = true;
appearanceUpdateRequired = true;
} else {
sendMessage("You need 35 mining!");
}
}
public void mithmine(){
if(playerLevel[14] >= 50){
sendMessage("You mine some mithril ore!");
addItem(447, 1);
addSkillXP((125*playerLevel[14]), 14);
actionTimer = 40;
setAnimation(625);
updateRequired = true;
appearanceUpdateRequired = true;
} else {
sendMessage("You need 50 mining!");
}
}
public void addymine(){
if(playerLevel[14] >= 70){
sendMessage("You mine some adamantite ore!");
addItem(449, 1);
addSkillXP((150*playerLevel[14]), 14);
actionTimer = 40;
setAnimation(625);
updateRequired = true;
appearanceUpdateRequired = true;
} else {
sendMessage("You need 70 mining!");
}
}
public void runemine(){
if(playerLevel[14] >= 75){
sendMessage("You mine some runite ore!");
addItem(451, 1);
addSkillXP((500*playerLevel[14]), 14);
actionTimer = 40;
setAnimation(625);
updateRequired = true;
appearanceUpdateRequired = true;
} else {
sendMessage("You need 75 mining!");
}
}
Have fun with your mining