Evgeni Nabokov has been a fairly pedestrian goaltender since the lockout, but he has drawn a significant salary:
I've normalized his salary into 2009-10 dollars, where the average win from a goaltender costs $2.8M (marginal wins per marginal dollar), while the average win from a UFA skater costs $2.3M. The Sharks paid $3.1M for 8.4 wins from Nabokov - had the Sharks spent more efficiently, they could have had another three wins over five seasons.
As Craig Anderson has shown, the market for goaltenders is hardly efficient. Nabokov has made a lot of money for being pretty average, and at age 34, is on the wrong side of the aging curve. A 2-year deal worth $7M would probably give the buying team reasonable value, but Nabokov will probably want more years and more dollars given that he's coming off the best season of his career.
As for the Sharks, I think their plan should be clear: put together a goaltending tandem of Thomas Greiss and a bargain basement signing, and use the leftover money on Joe Pavelski!