When you say you have recently invested into it, do you mean you have gone full steam ahead without planning how to advertise? Might want to get some planning done first.
Maybe try advertising on the UKBF? Get an ad on the right-hand side. If you're looking for cheap ways, perhaps you should join lots of IT forums and just be present giving helpful and useful advice. After some time, people will begin trusting you and as long as you have your signature set, you should start seeing a return for your good deeds.