The one last thing that I would personally
suggest before you start spending money
is to try out this stuff if there
is any way you can have access to it.
Look in you area for any folks who are making
sound with modular synths and get a feel
for the basic building blocks. Go to your
library and read all you can.
Seek out Allen Strange's book:
Electronic Music: Systems, Techniques and
Controls (2nd edition) It's out of print
but my local library has it.
Have fun and experiment!
My (as they say) 2 cents worth