The Lancashire club booked their place in the Manchester showpiece by beating Leeds Rhinos 22-12 on Friday evening.
It was an emotional night for Tomkins, as it was his last home match for Wigan before he completes his move to the New Zealand Warriors.
He tweeted: "Sooooooo glad tonight wasn't my last game in cherry and white! Can't wait for next week, the final all the fans wanted!"
Tomkins has already been involved in one Grand Final triumph, having been a tryscorer in 2010 when Wigan beat St Helens 22-10 at Old Trafford.