Paypal allows chargebacks and people have scammed bitcoin sellers through chargebacks. Generally anyone directly selling bitcoin using paypal charges more than market price because of this. However, you can fund a virwox account with paypal, then buy linden dollars, then sell the linden dollars for bitcoin and withdraw the bitcoin. This link explains how to do it.
http://www.deepdotweb.com/buy-bitcoins-with-paypal-credit-cards/If you are happy to pay over market price you can search ebay for bitcoin and find sellers there.
