As far as I know, Clippers tried to get Brand, Magette, Randolph, Buke, and maybe Josh Smith but they never offered him an offer sheet as soon as Hawks said that they will match any offer. They got Davis and Camby.
Warriors thought the same thing about Josh Smith, Iggy or Okafor so they never bothered. Plus overpaying for them means not being able to re-sign Monta and/or AB. They went after someone more realistic like Brand and Arenas. They ended up with Magette and Turiaf. However, By landing Turiaf, Warriors didn't think they have enough to sign Lou Williams so they went the cheaper route and ended up with another Williams....Marcus.
The Sixers went after Josh Smith and Childress, getting them both means Iggy would be out but because Hawks saying that they will match (even though Smith says he would like to play somewhere else) they got Brand instead with the intent of re-signing Iggy, more importantly now that Childress is leaving for Greece. They ended up with Brand.
The fact that Ellis and AB got no offers was because Mullin was very vocal that he would match. As for the Grizzlies, they have no intent of signing any free agents (not actually sure what that franchise is doing).
Warriors should not be faulted by the fact that they didn't land unrestricted FAs Brand or Arenas. They offerred them mucho money, but they just didn't want to be here.
Clippers = Davis, Camby
Warriors = Maggette, Turiaf, Marcus Williams
Sixers = Brand
You have to note that Clippers lost Brand and Maggette; Sixers didn't lose anybody but still have to re-sign Iggy; Warriors lost Davis but still have to re-sign Ellis and AB.