First, a draft trade value chart; for example:
Draft Countdown - Trade Value Chart
Next, a list of draft picks by team; for example:
2013 NFL Draft Picks by Team
(And yes, I know it has not been updated for compensatory picks; it doesn't have to be exact)
Scenario One:
Pats want to acquire additional picks.
Best potential trade partners would be teams with plenty of draft picks, such as the 49ers (11), Vikings (11), Eagles (9), Dolphins (9).
Pats draft pick values: 640, 310, 128 (may be gone for Sanders), 10, 3
(1a) -49ers-
49ers draft pick values: 600, 560, 292, 210, 120, 45, 31, 28, 23, 6, 2
Pats could trade down five spots, moving their 1.29 for the 49ers 2.34, and pick up the 31st pick of the 3rd round - though they may need to kick in a bit more to make it happen, like next year's 6th.
Another possibility would be to trade the first in exchange for 2.61, 3.76, 3.95, and a 7th round pick. You like this if you believe this is a 3 round deep draft, the Pats would now have four picks in the top 100, even after losing their 3rd for Sanders; on the other hand if you're a quality over quantity guy, you of course hate this trade.
Pats draft pick values: 640, 310, 128 (may be gone for Sanders), 10, 3
(1b) - Vikings
Vikings draft pick values: 760, 720, 380, 165, 96, 56, 31, 19, 12, 5, 5
Pats could trade down, moving their first pick in exchange for 2.52, 3.85, and 4.101.
Staying with Minnesota for a moment -
Scenario Two:
Pats want to move up for an earlier pick.
Pats could trade up, moving their first two picks in exchange for 1.23, 3.85, and the 22nd pick of the 5th round.
Pats could trade up, moving their first two picks in exchange for 1.25, 3.85 and the 23rd pick of the 4th round.