Per Apple's (AAPL) March 2008 Quarter, Apple's 1Q08 Revenue by Product/Solution:
1. Macintosh: 47%
2. Ipod: 24%
3. 'Music-related' (Itunes ?): 12%
4. Software, Services: 7%
5. Other (including IPhone): 10%
*FYI, the iPhone accounted for about 1.5% of Apple's TOTAL 2007 revenues (when Apple sells an iPhone its accounting recognizes the revenue evenly over a period of 24 months)...Apple is the 3rd Largest seller of personal computers in the U.S., behind Dell (DELL) and Hewlett Packard (HPQ)
Full Disclosure: I own shares of AAPL.