Does this process ever get easier?
Parts of it do, but on the whole, not really, no.
For me, every book is a new learning process. I never really have seemed to settled on "how to write a book." And, there's always some point at which I have an ah-ha moment that you'd think I'd have learned years ago.
BUT, that being said, there are a lot of things that do get easier. For instance, I no longer blink at the idea of writing 2,000 words in a day. Sitting down and getting started isn't the chore that it used to be (of course part of that may be because it's my job now in a way that it wasn't before, but I do find that a blank page no longer fills me with a low-grade terror.) I'm not scared I'm going to write myself into a corner. I trust my characters, my instinct, my story-telling, my audience.
One of the most helpful things about writing that I ever read was this idea of "killing your Muse." Stephen King wrote in his book On Writing that if you sit down to write every day at the same time, your Muse will find you. And you know what? He's right. For me, it doesn't have to be the same time of day any more (thank Goddess), but it does have to be every day.
My friend and fellow writer, Naomi Kritzer, and I have talked about the fact that if you get out of the habit of writing something every day, even as professional writers, it can be very hard to start up again.
When I first started writing, I set myself a very minor word count goal. I told myself I needed to write at least 425 words every day. I don't know where I pulled that number from, but it used to sit on my desk. I didn't always make it, life being what it is (and I had a full-time job then). But it was a good discipline to shoot for that. The more words on page, the more progress made.
Also, it helps to know that some days are just hard... for everyone. I interviewed Neil Gaiman for Science Fiction Chronicle several years ago, and one of the things he said that really stuck with me is that he had days when writing was really difficult, but when he looked back at the words he couldn't tell which were the hard ones to write and which flowed like honey from his fingertips. Words are words and words on page are progress forward.
So, no, things don't necessarily get easier, but writing every day helps.