Software:
KPG-101DK - P.C. Programming Software for TK-2170/3170/3173 (Windows® 98 SE, 2000, XP, Me compatible)
You will also need a KPG-22 programming cable (can be found on eBay relatively cheap.)
Batteries:
KNB-35L - 1950 mAh, 7.2 VDC Lithium Ion battery
Google "KNB-35L" and you should get a bunch of places that have them. Or you could check eBay or find a local Kenwood dealer.