Put the spline drive socket into the bolt and give it a good clout to break the seal of corrosion,crack them all off and use airgun or drill to unscrew or youll be there forever did this and every bolt came out intact,make sure to run the m7 tap through all the threads to clean them ,on reassembly i reused the original bolts with thread lock 
Cheers bud, good shout with the 7 tap, did you round off any bolts? Because that's my nightmare!
You can get new bolts from eBay,
But you need to match them with the current ones you got,
Some Marked M7 and some Marked bbs VS
Ideal cheers bud, il keep an eye out for those markings?
I'm about to strip some split rims, I've done a bit of searching for info and found myself on the Wheel Whores forum. In the split rim section there is a couple of stickies threads about stripping, refurb, rebuild and suppliers.
Take a look, although some of it is a bit OTT
http://www.wheel-whores.com/forum/viewforum.php?f=7&sid=83401459700b11c6d787fc70df86056a
I did have a quick look on there, will look again. What wheels are you splitting? Will be good to hear how you get on
Mine are the same as these although I didn't buy this set
http://forums.vwvortex.com/showthread.php?5793982-FS-16-quot-STAGGERED-3-PIECE-VOLK-GR-C-sI doubt the bolts will be titanium as its an expensive material, more likely 12.9 steel, chrome plated from new, replacements will be around £100 for a full set. If they all come out ok you could have the bolts refinished and chromed.
The originals will have loctite on them. Make sure the socket fits really well, use heat and it well help release them.
Titanium and stainless versions are available as replacements but they are harder materials, more likely to damage threads and if not properly lubricated could easily get stuck and would be a nightmare to drill out.