I've only played with Blender a few times just so I know how it looks and so that I can talk about it without guessing. 3ds Max is my primary program and it's difficult to measure in it also. There is a helper tool called a "tape" that you can snap from vertex to vertex to measure. But is has no dimensioning tools like Sketchup and CAD programs. It's not a fault in the programs, I think that's just the nature of mesh modeling. It's not driven by dimensions and constraints (not parametric) so you learn workarounds to get things the right size.

FYI, it took me two years on 3ds Max every day to feel like I could really model what I needed to. It's very powerful and very difficult to master. If you stick with Blender, it will get easier each time you touch it. In no time you'll have it down. It doesn't get any easier than Sketchup. But that's part of it's downside I think. To make it that easy, you have to give up a few things.

Let us know if you have any more problems.