Posted: 09/04/2014 at 17:18
Yes, some of the bigger Halfs do have pacers. Think there used to be a list of which events had RW pacers on this site somewhere but if may have got lost/binned in a site upgrade.
If you've got a particular event in mind, check the race website; I'd guess if pacers are provided it would be included in the race details.
Otherwise, do you run with a club or friends? If so pair up with someone who can pace you/do the maths for you.
Print out a pace band with required mile split times so you just have to compare what it says on the band to what it says on your watch.
More expensive option, get a gps watch with a virtual pacer which will tell you if you're ahead or behind schedule.