Our nine month old is eating more and more solid foods. I've got a bunch of those retort packs of baby and toddler foods specifically for her, as well as some dried pasta, ceral, arrowroots, etc. I also pack dried and ready-to-drink formula, enough for a day in my day pack, and three days worth in her BOB. She's starting to eat more and more of the same foods we do, so that makes it a lot easier. (The bigger challenge I see now is how to cook when I'm on my own with her, without a screamfest ensuing.)

Here's a look at what I typically carry for her, in terms of feed, on a day hike, along with bottle fixings. (Not to mention sharing my food.)

http://www.youtube.com/watch?v=fupEG2jTy0k

As for containment, we're still using the strolled and car seat, but I'm soon going to pull out the baby backpack, that also works as a highchair. Once our son got motoring, a stage we're just entering with out daughter, we mostly tag-teamed him, letting him roam and explore, or distracting him with toys, etc. We used a tent for sleeping, and secured the zips by simply putting them at the top, out of his easy reach.

I echo MDinana's recommendation to do trial runs in the backyards. It's a great way to get everyone comfortable and familiar. When my son was little, we used to do afternoon story time and naps in the tent in the backyard as long as Mother Nature cooperated. it was fun, great fresh air, and it got him used to sleeping in the tent.