I wasn't sure where this would actually go, and figured that since it had to do with language it might go under the literature section.
The thing is, I've recently started to want to learn sign language. I think that it would be a good skill to have, just like learning any other language. The thing I want to know is how long it usually takes to learn and get a good grasp on sign language. I'd also like to know which method of learning would be best (I'll most likely buy a book that teaches it from the bookstore and just learn it on my spare time).

I learned from just checking out YouTube videos and getting help from friends who use sign language. Honestly the YouTube tutorials are extremely helpful, so I'd suggest that. There are also many websites that offer free sign language lessons and such. Basic rules and signs, all that good stuff.

Probably a few days. I learned it within a day though. Best way to learn is too find who actually knows how to do it. Try conversing with someone just using sign language, that way you might be able to farmiliarizw yourself with it.