If you want an electric guitar for under $100, you really only have one good choice, and thats
this Kramer Focus VT111S deluxe, you can pick up the standard for about $10 less and a fatboy for a $100.
Here's some harmonycentral reviews
Honestly though, you would be much better off to just wait a couple weeks and save up enough money to buy yourself something in the $300 range and an amp to go with it.
It also doesn't hurt to have money for a decent stand, a pick holder, some picks, maybe a strap, some fast fret juice and a spare set of strings for when you inevitably break one on a sunday when your local music store is closed.
You will outgrow a $100 guitar pretty quickly. The $100 guitar segment is for lazy parents to buy their kids a guitar for their birthday so they can get them off their back. $100 guitars will sound worse, have crappier hardware and be a lot less durable and more susceptible to you damaging little things like knobs than a $300 guitar will. The tuners will be garbage, expect to tune the guitar every 2 songs or so.
I'm not saying they're complete crap. $100 will get you a lot more today than it would have 10 years ago. Most guitar gods you listen to learned on a lot worse. You can always upgrade the hardware if you so desire, and a good setup will go a long way on any guitar.
I learned to play on a beat to hell 2nd hand Epiphone strat copy that was in far worse condition than that Kramer Focus will be. Just keep in mind that I also got frustrated with it after about 3 months and bought a new guitar.
Edit: One more thing, which I'm sure has been brought up before, is that if you insist on buying a $100 guitar, you should really check out scratch and dent items. Music shops usually get shipments of guitars, and some inevitably have scratches or dents, maybe broken hardware, and they will fix them and sell them at a discount. If you could scrounge up another $100 you could probbably get the equivalent of a $300 guitar that just doesn't look as pretty as a brand new one.