AA,
Blackpool's probably the closest you'll get although still over 20 miles from Blackburn! There is however a station right next to the airport (Squire's Gate) with an hourly (?) service into Preston from where you should be able to get another train to Blackburn. Not sure what the landing fee is as the planes I fly are based there and the landing is included in the hourly hire rate. Try
www.blackpoolairport.com/ for this and other details.
Enjoy the low level route if going that way; remember to get (and set!) the MAN QNH when using it though!