Can you let us know what your trying to achieve, in addition to what your going to use, if your talking about platenum resistance thermometers then its a little more complicated to implement, if you simply need to measure temperature at home say and to within a 1/2 or less degree then there are loads of SPI or I2C devices that would be far simpler to interface, or even some of the one wire devices from Microchip
I would agree. I've got 5 x ds18b20 paralleled up and connected to the GPIO4 on the Pi. This has got to be the simplest way to connect temperature sensors.
If you are not used to driving these devices I would suggest using an external datalogger device and reading the contents back in to the RPI . This would allow you to concentrate your programming on the storage and dissemination of the readings via the RPI. If you wantto build something how about using the MAX6675 that has been mentioned on E14 recently and will connect to the SPI on the PI
