If you really don't like tax here in the UK, you could just buy a car older than 1974 - you subsequently get historic tax which is free, whatever emissions it spits out
In my area it's 115.9p for unleaded and 123.2 for super at the moment.
The petrol price I can deal with but the tax is ridiculous considering that the roads here are really bad.
Around the same here (got back from holiday to find it'd gone down by a penny, 114.9p.) Diesel is by far the more economical here though - it's only a couple of pence more (sometimes the same) and considering how many more miles on average you get out of it...
Sad fact is though there's no competition, if they charge more you have to pay more. There's not going to be a huge desire for anyone in the car industry (and certainly not the fuel industry!) to spend millions on risky projects with alternative fuels when they're still making plenty of money at present.
In terms of dealerships, yes they are a rip off but we all know that! People still go though because of the guarantees and suchlike you get with a vehicle purchased from there. It's fine if, like root and many others here you can diagnose faults pretty quickly and swap brake lines / discs / pads and suchlike out whenever they need replacing. If you're like me then the time it takes to read up on how to fit the things, get the right tools and fix them (not knowing how to alraedy) is pretty prohibitive.