As of 07/2010 a 2000 silver proof set retails for about $35. Your proof set's package should say that it's a "Prestige" set. Anything else contains copper-nickel coins, not silver and sells for about $14.
The 40% proof silver set was a 3 piece.
The 14-piece silver proof set is currently valued at $44.00. Issue price was $56.96. A 5-piece Silver Quarter proof set is $38.00. Issue price for this set was $32.95.
The U.S. Mint did not issue a 1979 Silver Proof set. None of the coins contain any silver.
With original Mint packaging retail is $30.00 for a Silver Proof Set
No silver coins were included in the 1973 Proof sets.
Numismedia lists a 1999 silver proof set with a retail price of about $315 as of 04/2009.
A 1985 proof contains no silver coins.
It is possible, but it depends on which set your coin was in. If your coin is in a standard proof set, it contains no silver. On the other hand, if your coin is in a 3 coin silver proof set with the dollar, half and quarter it is 40% silver. If your coin is loose, you should be able to look at the edge, if it is silver it will usually look more white compared to the non-silver version which will have a stripe of bright red (or sometimes pink) copper.
The 3 piece 40% silver clad proof set is $29.00 issue price was $15.00.
No 1972 silver proof sets were made, only single Eisenhower uncirculated & proof coins were struck in 40% silver.
The 7 silver coins in the set have a combined weight of 1.33823oz of pure silver