If going by train then the ground is about a 15 minute walk from the station (map).
Sheffield United fans still have a bit of a reputation, so I would be careful about where you choose to have a pint. Some places suggested for away fans on the Football Ground Guide are the Golden Lion (map), which is said to positively encourage away fans to visit, and the Earl (map). These are both quite near the ground. An option near the station is the Norfolk Arms (map). Not far from there is one of the inevitable Wetherspoons, the Bankers Draft (map). Definitely to be avoided are the Sheaf House, Railway Hotel and Cricketers.
Last time we played down there most of us ended up in the Old Queens Head (map), the oldest commercial building in Sheffield apparently. It's hidden away behind the new bus station and so doesn't get that busy, plus it does decent beer and food. And they've got a beer garden (well, beer yard anyway) in case it's a nice day.
Football Ground Guide
Pub guide (by Burnley London supporters!)