Made it this time! Not looking at others' answers... Also, I've posted my guess for what it is listed in the book, and for what I would probably charge for it, as per the rules of this game.
1) Belt of Battle - book guess: 1000g. My price for +2 init, 1/day pounce: 3000g
2) Belt of Growth - book guess: 400g. My price for 1/day enlarge person belt: 1000g
3) Desperation Chain - book guess: 3000g. My price for a better-than-auto-quickened 3rd lvl spell when you need one: 9000g (still less than 1/3 of the price of a quicken rod, since uses slotted space and only works on low-level spells, but it does give you an immediate action...)
4) Healing Belt - book guess: 400g. My price for a couple of decent spells: 1000g
5) Belt of One Mighty Blow - book guess: 400g. My price for a 1/day +tiny damage: 750g
6) Cord of Favor - book guess: 400g. My price for +crappy skill and 1/day sub spell: 750g
7) Belt of Ultimate Athleticism - book guess: 4000g. My price for duplicating rogue special ability for multiple crappy skills: 6500g
8) Belt of the Wide Earth - book guess: 1500g. My price for ok ability + sub teleport: 3000g
9) Belt of Priestly Might - book guess: 4000g. My price for +2 str belt and +1 nat armor ammy (wrong slot) for very few folks only: 5000g
10) Silkslick Belt - book guess: 1500g. My price for rare-use ability + 1/day boost: 3000g