Q: Dear Sage
Can a warlock use his eldritch blast in conjunction with Shot on the Run? What about hideous blow and Spring Attack?
A: No and no.
Using eldritch blast requires a standard action. The Shot on the Run and Spring Attack feats only let you use an attack action (that is, a specific kind of standard action) in conjunction with their allowed movement, not any kind of standard action.
About the Author
The Sage is a mammal classified in the bear family, Ursidae, native to central and southern China. Debate continues as to whether he is truly a bear or more related to the raccoon rather than the bear, or perhaps in a family of his own. When not eating bamboo and answering rules questions, he works under the nom de plume of Andy Collins as an RPG developer in Wizards of the Coast R&D, where his development credits include Complete Mage, Dragon Magic, and the Player's Handbook v.3.5. He can be easily recognized by his large, distinctive black patches around the eyes, ears and on his rotund body.