If the Inspiron 6000 will fit, the E1505 will. The size varies by only about a quarter of an inch.
It's hard to find a good bag. I wanted a bag, more like a map bag, that is with the notebook hanging vertically. I've gotten sick of the sideways bags over the years of carrying them. A lot of reviews recommended the SaddleBag Pro from Kensinginton. But it says it only has an interior dimension of 13.5" so I wasn't sure if it would fit the E1505.
I ended up with a backpack. Specifically the LowePro Tropolis 1250. Bought it from Dell for about $45 when I ordered by laptop. (I see it's now $69.95, but it was on sale back then, anyway). This thing would be awesome if they'd put hooks on the side and made it into a shoulder bag.
But even as a backpack, it's very nice. Good fit for the E1505, and there is good layout of pockets and such internally. Lowepro makes professional camera bags, and has a lot of experience in that area, I'm glad to see them move into laptop cases. Also unlike most backpacks, it's style is for adults not kids.