Here are some links of some RAM modules by good companies:
G.SKILL 2GB (2 x 1GB) 200-Pin DDR2 SO-DIMM DDR2 667 (PC2 5300) Dual Channel Kit Notebook Memory - Retail
$37.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231116
Out of 261 reviews, 234 people gave it 5 stars, 13 gave it 4 stars.
Kingston 2GB (2 x 1GB) 200-Pin DDR2 SO-DIMM DDR2 667 (PC2 5300) Dual Channel Kit Notebook Memory - Retail
$39.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16820134555
Kingston makes great memory modules. Typically, I find that they're overpriced, but these are actually priced reasonably.
CORSAIR ValueSelect 2GB (2 x 1GB) 200-Pin DDR2 SO-DIMM DDR2 667 (PC2 5300) Dual Channel Kit Notebook Memory Model VS2GSDSKIT667D2 - Retail
$39.99
http://www.newegg.com/Product/Produ...1309121117+1309221136&name=DDR2+667+(PC2+5300)
Corsair is another great company. I have had some of their desktop memory in my 1.5 year old desktop, and not any problems.
Crucial 2GB (2 x 1GB) 200-Pin DDR2 SO-DIMM DDR2 667 (PC2 5300) Dual Channel Kit Notebook Memory - Retail
$44.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16820148086
People on here rave about Crucial, so here is a link to some of their memory modules. I personally wouldn't spend any extra money for the crucial memory. They certainly aren't the top dog they used to be a few years ago. There are other brands, like Kingston, OCZ, Corsair, Patriot, G.SKILL, mushkin, PNY is decent if you're not overclocking.