Hi I was just wondering if anyone knew any good techniques or routines to put on weight in muscle, I've been underweight for years now and I'm on a good work out plan but its only gotten me ripped and toned but I would prefer to gain muscle weight before toning, any tips, tricks or even any websites on how to gain a quick 25lbs in full body muscle weight would be greatly appriciated, thank you

Lots of info on the net. Here's a couple of pdf links to files you can save to your comp.

http://www.nsca-lift.org/HotTopic/download/Strength%20Training%20for%20Muscle%20Building.pdf

http://www.coach.ca/admin/pdf_admin/pdf/Nutrition_GainWeight_eng.pdf