Take a look at ChucK's baby brother 'miniAudicle' if you just want to try the water. It's fun ... you'll have sound in a couple minutes!
http://audicle.cs.princeton.edu/mini/
For a book on theory try "Computer Music" by Dodge & Jerse. The Curtis Roads books are v.good too.
I'd just get started improvising with whatever! and then as you get time, check out the (many!) software options and see what fits your mental/musical personality. It's always a battle not to get over-lost in the tech side at first because that can cramp your creativity ... and even your motivation.
Finally, for a DEEP course in EM try The CSound Book. CSound will let you make ~any sound you can conceive ... but it's a heavy lift. (More for studio than live.)
For a book on theory try "Computer Music" by Dodge & Jerse. The Curtis Roads books are v.good too.
I'd just get started improvising with whatever! and then as you get time, check out the (many!) software options and see what fits your mental/musical personality. It's always a battle not to get over-lost in the tech side at first because that can cramp your creativity ... and even your motivation.
Finally, for a DEEP course in EM try The CSound Book. CSound will let you make ~any sound you can conceive ... but it's a heavy lift. (More for studio than live.)