IDE and SATA are styles of HDD interfaces. IDE was mainstream for years and is slowly being phased out. They have the long narrow jacks that plug into pins on the actual drive itself. SATA II is becoming the new standard, and it's jack is a short, very narrow connector. SATA also requires that your MoBo support SATA devices.
There are other makes/models/sizes of Drives at both Tiger and Newegg, so if you just do a search for IDE or browse through their Hard Drive area and select IDE, you'll see much more. Hope it helps!
Most cheap ones come around 40 to 80GB and they cost $40, but the 120GB costs $50 or so and the 250GB cost $65 or so. So the decision is yours, however, do not get an excelstor hard drive, ive had nothing but problems with mine.