There are quite a few mics available in the $100 range. The MXL V67G and the B.L.U.E. Spark are among my favorites. AKG Perception 120 is a valid option. Aren't condenser mics better? That depends on whether you think blondes are better than redheads. They are *different*, not *better*. Condensers and dynamics are like the yin and yang of microphones. Is a Gibson *better* then a Fender? They use different approaches to turning sound into an electrical signal. Any pro studio worth a damn has a bunch of both. There are also ribbon mics, which are a specialized subcategory of dynamics. There are also crystal or ceramic mics, more often used for CB and shortwave radios than music recording.
Forgive me for a little oversimplication, but dynamics *tend* to be less sensitive than condensers, and to have a weaker output. This means that a dynamic will benefit from a powerful, noise-free preamp, in other words, a lot of clean gain. If you have a cheap preamp, condensers may work better, as you don't have to turn up the gain on the cheap preamp/mixer, which tends to increase self-noise. On the other hand, some of the greatest recordings in history have been recorded with cheap dynamics and expensive preamps.
The sensitivity of condensers, especially those with small (therefore light) diaphragms, can reveal fine details of great instruments and great voices, but can also reveal ambient (background) noise, lip smacking, finger squeaking, and the fact that you had a carbonated beverage for lunch. They will also tend to reveal the bad reflections of a bad room, or the good reflections of a good room. Detail is not always a good thing. That's why they airbrush pictures of fashion models.
In short, if I was recording Pablo Casals on a $400,000 cello in a perfect room, there is no doubt I would reach for a condenser. If I was recording a high school girl doing a bad version of a Gwen Stefani cover with a $100 acoustic, I would start by putting up a dynamic. But- these are tendencies, not rules. Anybody that wants to learn recording needs to have at least one of each to start, because they are the basic tools of recording.
The C2000B mentioned above is a very good *fairly* cheap condenser. It's about $300 new, but you can find them for $100-$150 used. As far as cheap dynamics go, the good news is- the most expensive dynamics in the world (excepting ribbons) cost *hundreds* of dollars. The best condensers cost *thousands*. For dirt cheap, I like Behringer XM8500 ($20 new). In the $100 or less range, many, many folks will recommend Shure SM57, a cheap dynamic standard. I prefer the discontinued AKG D770 ($50 or-so on ebay) or the Sennheiser e835. The top of the line dynamics tend to be ruled by about 4 mics- Sennheiser MD421, Sennheiser MD441, Shure SM7b, and Electrovoice (EV) RE20. Most of them can be found for $200-$300 used. For any of those, you'd better have a pretty good preamp. If you are just starting out, and money is tight, I'd look for an MXL V67G and an AKG D770, but those are just *my* choices. If you stumble across an AKG C2000b for cheap, you could do a lot worse. I hope that helps.-Richie