I am sorry we can't help you with directions to Eugene from your neck of the woods, but when you want to fenture over to the coast (to beat the heat) which will be about 1 hour from Eugene, head on over to Florence. It is a great place to stay or visit. Lots to do and see with one of the best state parks for families (Jessie M. Honeyman) or anyone for that matter. Many other state parks nearby also.
They also have a nice 3 block waterfront area with a Mo's Restaurant and a great ice cream store called "BJ's" that makes it's own ice cream. The waterfront is loaded with neat little tourist shops.
The sea lion caves are about 11 miles north of Florence and the Heceta Head lighthouse is just up the road from the Sea Lion caves. You can tour the lighthouse and even the haunted GateKeeper's cottage if you time it right.
You can also go east from Eugene thru Springfield and hit the McKenzie River area which is absolutly beautiful and has campgrounds and lakes. I think it is about 1/2 hour from Eugene.
Okay, I better stop rambling now, I am off to work.
Have a great day and welcome to the west coast!