I've got some experience on several different microcontroller platforms including:
Microchip PICs
Atmel AVRs
Motorola HCxxs
TI TMS320LF24x DSPs
Systronix JStamp - utilizing aJile aJ-80<p>Each of these platforms has it's applications. Depending on how much money you'd like to put towards a devel environment, and what your goals are, I can probably point you in the right direction.<p>PICs are all about ease of use. To get started with PICs, you can get the schematics for a 16f84 programmer and software to program it from the net. All of the parts are Radio Shack accessible and can be has for $10-$20. The 16f84 chips are the bottom end of Microchip's medium grade MCUs and are the most popular for beginners. The devel environment is free from Microchip.com and the chips can be ordered there as well.
The PICStart Plus Development Programmer is $100 and will program all of the mid-range PICs. It's got a zero input force (ZIF) socket that will not break the legs off of your chips from going in and out of the programming socket repeatedly.<p>If you are looking for In-circuit debugability (ICD), Microchip sells an ICD for $100 that will program the 16f87x chips (upper end of the mid-range MCUs). This programmer/debugger is designed for in-circuit programming and debugging.<p>Overall, I find PICs to be very user-friendly and powerful enough to complete basic tasks effectively. If you stick with micrcontrollers a while, you will likely find that they won't keep up with your needs as you get into more complex control circuits. They are useful for small projects.
<p>The Atmels require a bit more programming ability, but reward it with greatly improved performance. They give more bang for the buck and offer larger, more powerful chips than does Microchip. There is a
free GNU C compiler for the AVRs and the devel software is free. The programmer that supports all of the current MCUs from Atmel is $80. This programmer has sockets for DIP chips (as would be used in a breadboard) as well as support for in-system programming. The board has integrated switched, LEDs, an RS232 level convertor for interface to a serial port, and is automatically upgraded by the devel environment if necesary.<p>Atmel sells an ICD as well for $200, though I've not used it.<p>
The HC08, HC11, and HC12s are not my favorite microcontrollers. The HC08s are very reliable and have had their bugs worked out, but the dev tools are akward and expensive. Stay away from 'em. As a side note, researchers at Motorola are develing a low power wireless protocol and were attempting to use the HCxx chips. They finally had enough troubles with them that they have now resorted to Atmels.<p>The TI chips are the most powerful of the chips by far, though to get a devel suite for them requires a minimum investment of $300. For your precious dollars, though, you get everything you need to develop in C. The DSPs far outperform any of the other solutions so far and the market demand for DSP programmers in high. The DSPs do everything another microcontroller does, with some additional features.<p>
If you happen to be familiar with Java, or are interested in going the object-oriented approach, I highly reccomend the JStamp. Its successor, the JStik is a little faster and has embedded ethernet support. Multi-threading, complex operations, and overall ease of programming are the key features of the JStamp. The cost is around $300 for a devel kit and $125 for each additional JStamp processor.