I've been thinking of making myself a sig and was wondering what programs you need to be able to do it if someone can tell me that would be great thanks.
Photoshop is good, but GIMP should work just fine too. PS isn't free but you can use the free trial for a month or so I think. GIMP is completely free though.
If you want to upload a picture however, do it via imgur:
http://imgur.com/