Just found a link to check when freeview HD will be available in your area, the link is
http://www.freeview.co.uk/freeview/Services/Freeview-HD2
But check what transmitter you are on, as because i used my post code, and I am the north of Brownhills, close to the South Staffs border and said I will get freeview hd at the end of march 2010, where as my parents are the other side of Brownhills, the Walsall Wood end, and said they wont get them until 2011, but if you check, the postcode checker thought they are coming of the Wrekin transmitter, where they are using the Sutton Coldfield transmitter.
I know there are several HD freeview boxes available at the moment, as you will need to change your freeview box to a HD compatible one to receive the HD channels, There are 2 in argos at the moment starting from £150, but as a guess these will get cheaper over the next year, as more areas will be able to receive HD.
Channels at launch will be BBC Digital and ITV Digital, with others to follow. If everyone remembers the big re-tune least year for freeview this was to make room for these high def channels.
I hope you find this info useful
UPDATE JAN 2011
I now have freeview HD, just before christmas I decided to get a freeview HD box, I had looked around and I found the Tesco have a clearance store on ebay, they selling reconditioned or item that just have been returned. All at approx half the cost within the store or direct on there website.
I brought the Technika model STBHDIS2010 set top box, now did read alot of reviews and these boxes aren’t the most reliable in the world, as I also got an extra 2 for my parents. They do suffer with problems coming on, ie if power has just been switched on the the set top box, but you dont turn it out of standby straight away, when you switch on out of stand by some times it wont switch on and display the epg or sometimes you get normal SD channels but when you switch to the HD channels you get sound but no picture. The easiest way to get working again is just to unplug and plug back in, then bring out of standby straight away. Even though I have these problems with this box, i don’t regret buying it as was only £35 with full 12month warranty.
At the moment December 2010 we have four HD channels, they are BBC 1 HD, ITV 1 HD, Channel 4 HD these are simulcasts of the normal SD channels, but if program broadcast in HD will be in full HD otherwise the boxes try to upscale the picture. The final channel is BBC HD, this starts broadcasting late afternoon and is different HD broadcast from the BBC, some are simulcasts of programs that are on in HD on say BBC2, BBC3 and a selection of other HD programs like documentaries.
I find the HD is well worth the upgrade as the picture quality is great my TV runs at either 720p or 1080i, so with either of these setting the picture is great. some programs look great other look ok, the best programs to watch in HD are mostly documentaries as-well as like the pixar, dreamworks films look amazing with great colours and definition. And even better I got to watch the Doctor who 2010 Christmas special in HD 🙂
Also just a quick reminder the West Midlands are the analog signal is getting switched off between April 2011 to Sept 2011, see this link for details of which transmitters and when the switch from analog to digital freeview in your area, this shows all different areas and regions over the UK.
http://www.digitaluk.co.uk/retailers/switchover_information/switchover_dates
Update:
I still have the tesco STBHDIS2010 box, this is now in another room, In the main living room we have upgraded to the youview by, by talktalk, which received all the freeview hd channels and also acts as a pvr, this is a great box, the one thing is that the unit has a usb port on the back but seems no way to transfer what you have recorded on the box to an external device, or even share over a network, which is a pity as this would make it a great box, see my full review of the youview box on my homepage.