There's a very diverse line of iPods that range from 1GB to 100+ GB. Some have more features than others. Go to the Apple website and find one that fits your needs!
The ipod now comes in many shapes, sizes, and memory amounts. There is a thirty gigabyte iPod that has video capabilities as well as MP3 playing abilities.
I don't think that 30 gig iPods exists because an iPod usually only come in 32 gig sizes. Since there's only 2 gigs more, this should fit your requirements.
There is a 30 gig Ipod which was casually called the Ipod Video. There are not many available in stores but many online retailers have places where you can find them. They are black and play both music and video files. It is a great product and very durable as well.