For basic wireless operation the Btwin
COUNT range are very good and great VFM.
As vicksters says though, if you want to know, "where I am and how far I have left to go", then you're getting into GPS units.
The most popular beginner unit* is probably the
GARMIN EDGE 200 which offers very simplistic navigation by way of user pre-loaded routes and can be had second hand for around £50 - £60, or new for a lot less then the RRP if you shop around.
*I still use the Edge 200 TBH as it does all I need and then some, so the need to upgrade for me is simply not there, but many do and that's when their 200's get offered in the classifieds
HERE