First-half strikes from midfielder Tonge and well-travelled striker Ward along with an inspired display from goalkeeper Paul Gerrard sealed United's success.
It as a particularly sweet win for Blades boss Neil Warnock who had been subjected to chants of 'cheat' by the Albion fans in the first meeting between the teams since the infamous 'Battle of Bramall Lane' in March last year.
Warnock came under fire after that game was abandoned when his team were reduced to just six men after having three players sent-off.
He was delighted with their success at the Hawthorns and said: "I thought it was a cracking performance. We really came of age in that match.
"Any team that finishes above West Brom will be promoted and to come to the Hawthorns, win and keep a clean sheet is very pleasing.
"We are getting better as a team and it was an excellent display."
On his reception from the Albion fans, Warnock added: "I was expecting more from the crowd."The win ended Albion's 100 per cent home record after six straight wins.
A seventh would have set a new club record and manager Gary Megson said: "No-one at the club can he happy with that performance.
"We did not do anything better than Sheffield United and we looked sluggish and did not defend well. We have to play better than that."
Tonge had stunned Albion after just ten minutes with a classy piece of finishing.
The 20-year-old played a hand in creating the goal himself as he exchanged passes with Ward before curling his shot beyond goalkeeper Russell Hoult from 14 yards.
United's lead would have been short-lived but for the heroics of Gerrard.
The former Everton keeper pulled off stunning saves to push away a header from Thomas Gaardsoe and turn a low 25-yard shot from Jason Koumas around the post.
When Albion did beat Gerrard, striker Rob Hulse could only fire into the side netting from six yards.
The importance of that miss, and the form of Gerrard, became clear eight minutes from half-time when Ward pounced.
Ward's strike was created by the pace and power of the United midfielder Michael Brown.
Brown raced clear down the right wing before sending over a cross that Ward calmly slotted home from six yards.
Megson sent on Lee Hughes and Danny Dichio to form a three-man attack with Scott Dobie.
But the trio could not find a way past the impressive Gerrard who frustrated Hughes by pushing his 53rd minute header over the bar as United eased to the top of the table.