Get a CMS, WordPress, getSimple, Drupal is great (requires a strong skillset), Joomla which has great off the shelf stuff but tries to do too much so gets to be a pain in the ass.
The nice thing about a CMS is to be able to set up internal templates for things like product detail pages. Once the template is built adding a page is as simple as plugging in product specific text and graphics into their placeholder areas.
This
SouthPeak Games | Dementium II for Nintendo DS
and this
SouthPeak Games | Trine for PC
are generated dynamically plugging in the non unique assets
Some of mine
Drupal
Stronghold 3
Two Worlds II - Enter Your Date Of Birth
Tap and Teach: The Story of Noah's Ark - Activities
Real simple one done in simpleCMS
Minor Lords