The other day I picked up a friends acoustic/electric guitar, tuned it up and started noodling a bit, and was amazed at the quality and sound it had. I liked it enough to ask him if he wanted to sell it since I've been in need of one. He said he paid $100 for it, so I told him I'd give him $120 but I wanted to do some research on it first. I really thought I was getting a great deal. I took a few pictures, and the next day I decided to take a look and see what they actually go for. It turns out it was a Kona, and they sell them at Walmart and Target for around $130 for that model. I called him immediately to tell him of my findings, and that I won't be pulling the trigger on that sale.
It shocked me a little bit, but they are great guitars for beginners if you want to start with an acoustic, which I'd recommend. They also have electrics, and starter kits that come with pretty much everything you'd need.
KE2BPK
The Guitars||and amplifiers
There are other good names too like Yamaha, Ibanez, etc, that go for around $100 as well as starter packages from other various companies (like the Luna Guitar kit I bought for my daughter a few years back that came with a small Line 6 amp, with some amp modeling), just take a look into Musicians Friend or Guitar Center, but judging from what I played on the Kona, I'd personally go that route, and recommend it to anyone just starting out. I've been playing guitar for over 30 years, and have taught many students, so I do have a bit of experience.