In the UK, dispatchers are often only turnaround co-ordinators rather than dispatchers in the true sense (I think the US equivalent is Redcap). Sometimes, they also have load control training, but in most ground handling agencies this is maintained as a separate function. At the larger airports, or within GA, dispatchers are likely to be more multi-skilled than at regional airports. In the first instance, best in the UK to treat the dispatcher as your first point of contact until you can establish what other duties they can perform.
As the dispatcher does not necessarily prepare the loadsheet, there is no real requirement for them to understand how it is put together any more than the captain of an aircraft needs to understand how check-in systems work, or to be able to drive ground equipment.