I have set up some band and a church sound system. I have a Yamaha AG Stomp for my acoustic guitar. I think that a processor is important because some places have bad acoustics and your guitar, no matter how good it is, will sound like a cardboard box with strings. I have heard this unit before and it is worth the $$. It has a good rep with any sound guy, except the everything has to cost over a grand guys. http://www.zzounds.com/cat--Acoustic-Gu … ects--2566
http://www.zzounds.com/item--BEHPAPACK2 I don't work for Zzounds
I like Behringer gear, some hate it, I think they are wrong. Behringer has a history of taking other peoples ideas, changing them slightly, and putting them to market very inexpensively. I have a mixing board, compressor, and sound fx unit that have lasted over 7 years and sound very good. Audiophile quality, no. Good enough for small venue, by far!!
This set up in the link has everything you need to do a show, except mics and cables.
For mics, I like Shure SM58's, they sound great and have a long track record in the industry. Sennheiser is making real good microphones, too. I haven't owned one, but I've heard them. They may be better and cheaper to buy than the Shures.
http://www.zzounds.com/item--SENE845S
Cables I don't get too concerned with because it is getting very rare to buy junk. The market is competitive, if you sell junk, no one will buy it. CBI cables are fine.
Again, I don't work for Zzounds and just used them for information purposes. They are a low cost outlet and competitive with the Musician's Friends, American Musicals, and Sam Ash's of the world. I hope this helps. Remember, you have to carry everything you buy, a little cart is a back saver.