I could go into detail, but why when there's a free eBook that's perfect for you. Check this out:
Also search will bring up tons of threads for you.
might want to try the "bulking" section
Stuff your face with whey, PB, chicken, rice, oats + lots of water.
i was in the same situation awhile back. Done a few searches on the forum and found plenty of good info!
chicken,red meat,oats,Peanut butter,tuna,cheese,nuts stuff like that. Was really suprised at the amount of protein thats packed into soya nuts They taste alright too.
I just went down to my supermarket and had a good look around. A lot of foods nowadays have good labels on them so you know how much cals are packed in. If i was still unsure i'd just keep searching till i found something online
Try keep the bulk as clean as possible, none of that junk food rubbish