I've been given a garmin etrex for christmas, it looks good, but I've not used one before, does anyone have any good tips on how to use it, before I resort to reading the instructions!

oh, me too! Just been on the first proper ride. Have you got a lead to connect it to the computer? If so get some software and its a lot easier to put in waypoints etc...

The quickstart guide in the manual was very useful to me, aside from that I've just been fiddling which seems to be doing the trick.

GET LOST

Then turn it on and find your way back ;-)

I've just ordered a handle bar mount, I looked at the cable for the PC but it was about £40.00

Go to www.pfranc.com for the cables.

Sorry, use pfranc.co.uk for the UK

Very much cheaper cables. I got a combined car power and data cable for about £20

I found it from your first link (http://pfranc.com/cgi-bin/pub/c_uk?pid=eD1)
£13.50 including P&P, I think I'll order one, what software are you using?

I use Anquet maps - the expensive option at £110 for GB South but frankly brilliant. The main difference is that it includes all height data

Is there a cheaper option for the peak district?

In my experience don't use it as your only means of finding out where you are. Make sure you have a compass and know how to use it, unless of course you are just using GPS for it's novelty value.

Standing on top of one of the highest paeks in the Lake District it asked me "are you indoors"! It couldn't find enough sattelites to know where it was and it didn't know how high it was. It did know that the Ullswater Steamer was travelling at 15mph though.

Oh in case you hadn't guessed, I'm not a big fan of GPS. They not a bad 'toy' though.

Gps is good but they are a bit prone to water ingress (get an aqua pack) and finding the battery is dead when the sh1t hits the fan doesnt help you to survive when your lost in fog you may as well cary a brick in your cammel back for all the good it will do you, it will have made you wish that you still had a bog standard compass and os map. I have a digital compass which is ok for a quick glance on the trail but i still prefere the old silvia compass ive had since i did orientering comp's which i lent (long term now) off the PE teacher.

I think most of us are organised enough to pack a spare set or two of batteries.

The fact is that GPS is far superior for MTB's - no stopping to look at your map, routes logged,all your bike computer functions etc, etc,

But YES still carry your map and compass JUST IN CASE!!!!

I've had one about a year now and I use it quite a lot for walking, cycling and in the car.

Although I have the data lead and etrex mapping software I still use it with an 'old fashioned paper map' as the detail of the GPS map is limited away from the roads. The main function I use is the OS grid refernce in conjunction with map ( handy on featureless forest trails ).
You can set the GPS to record your route and if push comes to shove you can use it to retrace your steps.
If i'm in a remote area I usually mark where I have parked the car as a waypoint ( more useful than you might think...not that I would ever forget where I parked my car ! )
GPS does have it's limitations - some valleys and most heavily wooded areas will block the signal form the satalites and sometimes can be made worse in really bad weather.But even if you only get locked onto a couple of satelites it can still tell you where you are within a couple of hundred feet - better than nothing !If you have no signal at all move to more open ground ( if possible ).
I always take spare batteries and if out walking or climbing in remote areas a map and compass.
GPS one of the best toys I have bought myself in years and the best use I've found is out riding !

This site may be useful to you,and they sell accessories cheap too.