Depends on how much they're going to cost you. I was so unimpressed by the original three
Races of... books (Stone, Wild and Destiny) that I never bothered to pick them up. Eventually I was lucky enough to stumble across the slipcase gift set at an absurdly low price. I bought it and pretty much got what I paid for, lol.
There are some interesting bits and pieces here and there. The variant versions of the core races are pretty interesting (whisper gnomes and stuff like that) and fitted well with my homebrew. The racial substitution levels are also pretty neat. There are some funs bits of equipment and some of the feats are worth a look.
I don't like the new races, though, or the pages and pages of fluff. I'm a gamer who builds his own races and his own fluff and so gets little mileage out of those sort of things in published releases. YMMV, on the other hand.
By comparison, I found
Races of the Dragon to be stonkingly good, but then I have a homebrew with widespread draconic elements. I'm not fond of Eberron, so I haven't really looked at
Races of Eberron, but an Eberronophile buddy of mine rates it pretty highly, both from crunch and fluff points of view.
So, yeah, I'd see if you can get them for cheap
I'd also echo the comments above that - if you don't already have them - you should definitely get the Monsters series (
Draconomicon, Libris Mortis, Lords of Madness and, sigh,
Drow of the Underdark.) They're great.