For thermal paste - go with Arctic Silver 3, and follow the instructions on their site when applying
For heatsink - look at the Thermalright cooler if you can afford it, since they're highly efficient and will work will with lower speed fan to reduce noise. Otherwise, take a look at Vantec Aeroflow - still a competitive cooler, efficient, quiet, and won't cost you an arm and a leg
As to case fans - look at ones from Panaflo, which are of high quality and very quiet for the amount of air they push. Sunon, Vantec (some are rebadged sunon), and Sanyo Denki also makes high quality case fans
BTW, if you have those very restrictive stamped grills (often just a few holes) where the fans suck air, cutting them out would help a lot as well - less noise and more airflow.