Not to just change the bearing's.
But if you need to change the rubber mount's then u'll need em.
But the bearings are underneath the rubber mounts!
In addition to the bottom bolts (which are done up damn tight, you'll need a breaker bar), you also need to remove the brake caliper and the sway bar links.
Technically, the bottom strut bolts are throw-away jobs - you're supposed to discard them and use new bolts if you undo them. I can't say I've lost any sleep over that though.
If you run stock springs, then I wouldn't be so sure you don't need a spring compressor. Just make sure there's no pressure on the spring when you undo that top bolt or someone could loose a head. The other option is to undo the top nuts before removal from the car with the weight of the car still on the springs.
However, with spring compressors, the strut tops and bearings can be changed with the strut in place. Remove the top plate (from above the strut tower), jack the car until the strut drops down to full droop then use spring compressors give enough room to remove the strut top.
If you're going to go to the effort of new bearings, I'd recommend doing the tops at the same time anyway. They all collapse. New strut tops come with the bearings and are less than $100 from Holden.
