Is there any web site i can go to to get free sid/star, and ILS approach info, charts for all of the USA? Did a search and it seems they can only be purchased. Also, I plan on buying the add-on 737 package (PDMG 737?)(For FS2004). I was reading the reviews on it and it seemed to give hint that it has those charts in the FMC. Does this add-on have those charts?

http://www.myairplane.com is a free site that has the actual charts.The PMDG 737 has SIDs and STARs in the FMC yes, but you'll want to update the database by going to http://www.planepath.com ( for SIDs / STARs ) and http://www.navdata.at ( for AIRAC .. basic navaid updates ).I hope this helps.

Yep, try this:http://www.naco.faa.gov/index.asp?xml=naco/online/d_tpp