Virwox accepts paypal, but there are big fees. but if paypal is your only way it will work.
Make an account at virwox.com, you will buy SSL (Linden Dollars) then convert that to btc so the process goes like this
USD/SSL then
SSL/BTC
thats how you can safely buy btc with paypal.
You can also look at brawkster.com which lets you buys things for other people and you get the cash value in btc. Sometimes its buggy if you buy things from another country but thats also another way.