If you are familiar with compiling Bitcoin and so, you may also take a look at:
https://github.com/bitcoin/bitcoin/pull/5048The "addrindex" branch (first post) currently requires about 37 GB on mainnet, but this one is fully optimized for the purpose of getting unspent outputs of any address, so it should be less. Given the amount of responses and activity on GitHub, it should be solid.
Otherwise I suggest to use one of the APIs. Especially chain.com aims to be a reliable, ready-for-production data provider.