I'm here! I'm here!
Ok, let's see, how much bandwidth do we have?
Matt, there are several really good, feature packed, compact, multi-band, multi-mode, HF rigs on the market. For all the features, $600-$800 is not a bad price for a brand new rig. These same rigs can be purchased for much less used on several Ham radio classified sites. I'll supply some links below. In good used condition, expect to pay $300 - $600 depending on model, features and condition.
Ok, some talk about these radios. Most run 100 watts of power out. That's usually plenty. They all will talk in AM, SSB, FM and some digital modes. They have many memories that not only remember what frequency you were on but what mode you were using and can automatically retune an antenna matching unit. Most also will go higher in frequency than the regular HF bands. Some include 6 meters, 2 meters, and 440mhz.
If you are used to CBs, get ready for a shock when you see the sophistication of these radios. Some to look at are the: Yaesu FT-100, Icom IC-706 mkIIG, the Kenwood TS-50, the Alinco DR-70.
If you can't find a Ham radio store near you, get on the net. AES (amatuer electronic supply), Burghardt (SP?), Ham Radio Outlet, are the largest.
For mobile HF radio work, the antenna is a major compromise. DO NOT scrimp on the antenna. Be prepared to spend real money for a real antenna system. A mobil antenna tuner is very important. It allows the radio to transmit safely on frequencies above and below what the antenna is initially tuned to. You see, for a transmitter, the antenna length is related to frequency its transmitting on. When you change frequency, the antenna should be retuned for the new frequency. These ham radios have a wide range of frequencies to transmit on. Retuning the antenna everytime you move a few hundred kilohertz in frequency is not practical. The antenna tuner will not retune the antenna, it will retune the antenna system so the radio has a good match to transmit into. Makes whatever antenna you use much more versitile.
These new radios can control an automatic mobile tuner. See why I say be ready to spend some money?
Now, after having said all that scary stuff, you can get by for a while with a less sophisticated antenna system. Just realize its limitations.
These radio don't use knobs like older radios did. To change parameters, you have to get into a menu and change settings that way. A real bother while driving and trying to adjust squelch, filters etc. Most folks find some basic settings that they can live with in most situations and leave it at that, changing things only when really neccesary.
Here are some great places to find info. Some are sites just like the IFSJA, with different areas devoted to different subjects. Newbies are welcome by most, basic questions are usually answered well by folks interested in helping.
Those ought to keep you busy for a while. eHam has some really good forums to read through. Lots of great info there just by reading through the posts in the various forums. You may see some of my dumb questions there.