Start by reading John Long's "Climbing Anchors" :
http://www.amazon.ca/Climbing-Anchors-2 ... 532&sr=8-2and then "Mountaineering; Freedom of the Hills":
http://www.amazon.ca/Mountaineering-Fre ... 567&sr=1-1and then go climbing with someone who knows what they are doing (it can be hard to find someone fitting this description sometimes) or hire a guide. Ask lots of questions and practice knots and things at home until they are second nature. You are not ready to take friends out climbing for their first time yet, but after a lot of miles in your harness you could be.
If you are going to extend anchors over an edge, use 7-8mm cordage rather than webbing. Webbing is a pain in the ass to work with and it's not as abrasion resistant. Around here it can be useful to carry up to a 10m length of cord, although most cordalettes are a 20 foot loop. You will probably want to own half a dozen locking carbiners or so. That should get you through most bolted toprope setups around here.