I'm pretty into them. Right not I'm working on my crt .5. Lokk at traxxas trucks, HPI, Losi, Associated, etc. Maybe you want to check out an rc forum? The traxxas 4wd slash looks like a cool kit. If you want something fast get something brushless and get a lipo. A lipo is a great first upgrade. The turnigys at hobbycity are great, especially pricewise. Maxamps are bad. Hyperion lipos are the best you can get.
For a stock smaller electric truck with a lipo expect to pay around $300-$400 plus the cost of a charger. You can look for used vehicles at rc-universe, rc-groups, rc-tech.net, and a few other sites. If you end up with a nitro I would suggest buying your first one new so you can get good to tuning it.
If you want a monster truck or other big truck, there is a HPI Savage flux, which is amazingly fast and great for jumping. You can get the traxxas e-revo or E-maxx. Both have brushed and brushless versions. Brushless is wayy faster.
If you want to spend a little lest and can settle for a 2wd, look at a traxxas rustler or traxxas slash or traxxas stampede They are very popular and very refined trucks. Most of these come with a radio and even battery/charger. I would first upgrade the battery to a lipo, then look at upgrading the transmitter if range isn't what you expected or the motor/esc after the battery for more speed.
I'm not a big touring car guy, but look at associated and losi's cars.
If you want a smaller 18th scale, look at the traxxas mini e-revo. It is the best out of the box. No upgrades needed. Great for beginners, but it can't go on the terrain the other trucks can.
And finally, if you want to run around the living room, check out the 1/36 scale line from losi. Micro T, micro Destert truck etc. The lipo is a good first upgrade for this as well.
Here's some pictures of my crt .5. It has a brushless mount (used to be a nitro), traxxas jato shocks front and rear, and 2.2 truck Proline gladiator tires on rpm wheels. I had a mamba max speed controller/flightpower 3s lipo/Medusa 3300kv brushless setup but I sold all but the esc. I am looking for a motor now and I'll get a turnigy off hobbycity with my next order.
The shocks/tires looks BA 8)
And my old vendetta st.
video - http://www.youtube.com/watch?v=S32YX7e01cE
Check my photobucket if you are bored and have a ton of time for pictures of my other trucks I have owned over the years - http://s345.photobucket.com/albums/p382/metallover1/