When I first considered entering the world of indie publication I searched for a British-based service that could help me, but could not find one. Later I on I came across eBook Partnership, which is based in England and provides a very different business model to most such services. The common business model is for the aggregator to make their income from gleaning a percentage off a publisher's book sales and not charge for the service. The funding model at eBook Partnership is very different. You are charged (January 2014 rates) for the first four books a £75 set-up fee for each book, followed by £29 per book for each year that you keep that book being distributed by eBook Partnership. Or, if you know that you will be a prolific writer, you can pay up front for five books at £149, which means only paying £29 in the first year. eBook Partnership does not take any percentage of your income from the retailers (Kobo, Apple, etc.). So if Apple are going to pay you 70%, then that 70% will be passed on by eBook Partnership, who fund their business by charging for the conversion and distribution of your books.
An added attraction of eBook Partnership is the welcome addition of distribution to the major UK retailer Waterstones and to Google Play. Few aggregators include Waterstones and the only other one to include Google Play to my knowledge is the German company Xin Xii. A problem for the eBook Partnership model is that many publishers like to go direct to Apple, Kobo and Nook, which makes the upfront fee system harder to make your money back on, unless you are confident of selling enough of your frontlist and backlist to justify the fees (e.g., £290 per year if you have ten books with them).