This from the Microcontroller section of this forum:
http://arduino.cc/forum/index.php/topic,96716.0.html
ATMEL also sells programmers for their chips, guaranteed to work but then you'd need to learn to get the compiled .hex file from Arduino to load or use their software to write/debug... I would think it has some things better but it isn't cheap. Maybe they think you will buy enough chips, they give?
If you need loads of pins , maybe shift registers would be what you are looking for? Not too sure what they can be used for but they would seem to point in the direction of what you are looking for.
An Arduino makes a nice programmer. Setup a small board with a zip socket, or use the 6 wire ISP headerto your own board. A quick batch file calling AVRDude and its done in a few seconds. I made a small board that has 2 cables (2" long) that connect to the power header and the pins 8-13 header and it has sockets for 20 or 28 pin chips. (ATtiny2313 & ATMega328 are what I have programmed). It has 2 sockets and a 16Mhz resonator for the 328. Except for a chip I fried elswhere it has never failed to program when I give it the right chip description. (tried to program a 328 using 328P, different signature...)
Create a batch file with the 2 AVRDude commands - one to set the fuses, and one to load the hex file. It really is pretty painless.
You need the 328, 3 caps, a 10K resistor and clean power...