We have booked 2 apartments in a townhouse for our holiday on the Costa Tropical this year through 'Owners Direct', which the other poster has already mentioned, we have previously always gone in hotel/apartment complexes but after two years when the accommodation was not up to standard we decided to book our own independent accommodation. The benefits of this are that we have been given the owners contact details, someone who lives here in the UK, and so have been able to email and call him for any further info and special arrangements we need, and he has sent us loads of useful details regarding the area we are going to, which restaurants are the most reasonable, and how to use the local buses etc. However, if you go for this type of accommodation you will need to book your own flights and transfers, though in our case the owner of the property arranged a transfer from Malaga for us.
'HolidayRentals' and 'Homelidays' are two other sites you might also want to look at.
And you can easily research the exact locality of the accommodation given by looking it up on google maps, though most give the exact distance from the beach, shops, airport, town centre etc.