If they're in the UK or USA they can contact me and I'm pretty happy to convert. (Shanee753@gmail.com). We can trade face-to-face if you're near the south of the UK. I have a number of good reviews on independent which I can provide.
Generally I use the bitcoin-otc chat on freenode which seems pretty good.
Coinbase handled the recent surge in traffic pretty poorly. When prices tanked / fluctuated heavily, they turned off the ability to buy citing "a lack of bitcoin" and told users they could put in buy orders now for the market price on Friday or Monday. Two days later when the price is back up to ~$700 you can mysteriously buy again.
I'm not one for conspiracy theories, but USD liquidity has been extraordinarily frustrating over the past several days since most exchanges are foreign (and US bank wires take days to weeks).
I thought we were talking about converting to cash, not buying. I agree that the hard stop on buying is extremely annoying, and that makes coinbase a bad choice for playing the market. If you want to do fast transactional orders, CampBx is probably a better choice.
I have successfully used localbitcoins.com, using National Bank Transfer. Use their escrow service.
Note that you probably do not want to sell to people through paypal (they can easily reverse the transaction), nor to people though other easily reversible payment services.
Sell them to people for cash. I used to use MtGox to get a couple grand out here or there, but now it's too much of a pain. It depends where you are though. There are some decent Canadian options, and Coinbase is supposed to be good for Americans.
localbitcoins.com or bitcoin-otc.com (irc). Buy peer to peer and then sell to your non-technical friends or friends of friends with a 5-10% markup. It is best to not look at it as a "problem" but rather as a entrepreneurial opportunity.