will ddr2 ram work on a ibookg4

Depends if the ibookg4 supports DDR2 ram, please post your current system specs

Apple computers normally accept only branded (proprietary) memory. So, it may be DDR2 (don't know), but it might only work with specific memory. your best shot at finding (affordable) memory will probably be with Kingston.

Investigate at these two links:

"Memory Configurator" at Newegg.com http://www.newegg.com/Product/ProductConfigurator.aspx?Category=17&name=Memory-Configurator

And Kingston's memory compatibility page here: http://www.ec.kingston.com/ecom/configurator_new/mfrmod.asp?root=us&LinkBack=http://www.kingston.com

I put some Crucial ddr2 in my powerbook g4 1.67, works fine. But without knowing which iBook you have we can't tell you whether it takes ddr2. Look at this page: http://www.lowendmac.com/powerbooks.html
Scroll down to your iBook, click, look at the specs.

Alternatively if you are using OS X you can go to About this Mac in the Apple menu and it will tell you. Click on More Info if you want more detailed info about your RAM such as the Size, Type, Speed, and how many (if any) free slots you have.