There are many decent exchangers (ecardone for example located in the Czech Republic), goldexpay (located in Slovenia) from which you can buy LibertyReserve. Thats if you are from Europe.
LibertyReserve transfers are non-reversable (like bitcoin transfers), so make sure you really want to send that money before you send it, because you will not be able to get it back, and without a court order from the government of Costa Rica, LibertyReserve will not help you.
LibertyReserve however is not a scam, but there are many scam websites taking advantage of the fact that transactions are not reversable, so first find a reputable exchanger that fits your needs.
As the person above said, when you receive LR, they take 1% from your funds, but not more than 2.99, so basically if you receive over $299 (e.g. 5000) dollars in one transfer, you will not pay more than $2.99 in fees.
Could someone with experience with liberty reserve clarify what exactly they are? How do you receive them/spend them? I'm interested because it seems liberty reserve is the primary way to fund btc-e, which seems to have an average of 2% better rate than mtgox.
On the liberty reserve site I see most of the points of sale are based in nigeria, a fact which does not give me great confidence in its non-scamminess.