Well, honestly, like I said if you look at real golf balls, the dimples are different sizes. Here's a good example:
You're not going to get that just from basic editing of a platonic solid. You would have to develop some sort of strategy of creating the various sized dimples in little square patches (using a plane) then merge the verts or edges, gradually building up a surface. Then bending into a circle shape. Since there are no real patterns to the dimples, this would be a bit difficult. If you're saavy with expressions, you could probably leverage one of the platonic methods and write something that would randomize the dimple sizes.
Not sure if you saw this post but here's someone creating one with the geosphere script mentioned earlier:
Creating a Golf Ball with Geosphere
His sample image needs more dimples and unfortunately the dimples are the same size...I think this basically follows the same idea as the other tut I posted but figured I'd post the link as a follow-up.
I realize you're going for the challenge of modeling it but I tend to look at things like "How detailed does this need to be? How close to the camera? How fast can I get this done for the client?" If I didn't use one of the aforementioned methods, I'd probably try making a displacement map for all the dimples and applying to a smoothed sphere. If I needed a detailed version...well, I bet the dimples would be fun to manually create in z-brush with a custom alpha.
"Terminat Bora Diem, Terminal Auctor opus."