I have memorial stones that lay flat on the ground over the graves, they are made of a precast material that is impervious to the weather, but look like stone. Surprisingly I recently found some pretty nice ones at walmart pet dept of all places. I plant bulbs around them so there are pretty flowers and nice greens there, I use daffodils in various colors and crocus.
Pet Memorial Stone
they are similar to this type, that site also has some nice little bench looking ones.

I also saw some at our local plant nursery.

I'd get some outdoor statuary of angels or cats and dogs and make a little flowerbed there.

On Etsy, look for engraved stones or rocks, they use rounded river rocks and are lovely and affordable, Lydia. I'm going to get one for each of the dogs and cats. We have a huge engraved one for Mariah Valentine but none for the others. I want small ones, like the size of my hand, for Autumn, Paisley, FreddieWheat, Tess and Roughy. I can cluster them around Mariah's.

I love the ones from Etsy, I haven't used them for pet memorials but for wedding gifts. Have loved them and gotten great responses.

I'm not a frequent poster, but wanted to respond to this post. First, I am sorry that you have lost so many treasured pets. Second, I was just looking for the same type of product earlier today and came across a site that has 'memorial stepping stones' thought I'd share the site with you. Some of the prices seem very resonable.

Here is a link that might be useful: Pet memorials

Thanks everyone for the links and ideas! I do want the names and dates on whatever I get... so I need something personalized. The ones on etsy are the ones I liked in the beginning, but to get names and dates mean I'll be spending quite a bit if I buy 3 and there's still the fear that a neighborhood kid will walk off with it (or toss it in the lake, which is what I suspect happened to my swirly green bowling ball I had in the yard).

Welcome to the KT Mar_dee!

Here is a link that might be useful: Some nice memorials here too

Oh, wow. I guess I've forgotten what it's like to have people/kids around.

Could you cement down whatever you decide to go with? I can't stand the thought of something like that going missing.

I've been pleased with these "stones" from Walmart and they're not too pricey. We have one for each of our deceased pets.

Here is a link that might be useful: personalized stones

Thank you for posting this Lydia.
We lost my sweet girl Miss Oct 16th. We intend to get a marker for her this spring too. I've looked on eBay and everywhere I can think of trying to make a decision.I would like something flat, don't know what we will find for sure but this gives me more to choose from.
Good Luck with your search, I know its got to be just "perfect".

We lost our beloved husky and two cats in the same year. It was overwhelming. When we lost our dog it was in September and we just needed to get out and take a nice long drive. We ended up in the Wisconsin Dells at a wood carvers place that we frequent anytime we're up there. He made us crosses, carved their names and such and now we have this great looking cemetary out back. I have always liked the simple look of crosses in a cemetary and this was perfect. We had to put tar on the bottom 10-12 inches that went into the ground, they've been up since 2006 and as they age they just get prettier.

When my cat Sparky was dying of kidney failure, I let her outside to walk around the yard. Sparky had been my pet for over 20 years, she'd lived with me through a divorce and tons of heartache, finally a good second marriage and two beautiful daughters. I noticed she laid down in one spot by a fence. I decided I'd bury her there. She picked her own grave, or so I thought. I buried her there and left a piece of brick to mark her resting spot. The next spring I planted Bleeding Hearts and in the fall I planted bulbs. It made a nice little flower garden that has bloomed for years.

I don't have a lot of issues with the neighborhood kids.. but there are a lot of pre-teen boys and you know how they can be when they get together. We could cement something down if we needed to.

I just found this nice staked plaque that could work with all 3 pets names and dates. I think we could put it far enough in the ground that it would be hard to pull up. Lots of other really nice memorial things at this site.

Here is a link that might be useful: Big hug memorials

I engrave into stones for memorials and other things, very reasonable in price and ship. please take a look at my site Lydia there is a picture of a pet memorial I did last summer for someone that put three pet names on one with a big heart around their names. It was real nice.

Here is a link that might be useful: Gifts In Stone

I had a friend who lost 2 of her beloved doggies-like you-they were buried in a small flower garden out back of their home. What she did was take their 2 metal dogfood bowls to an engraver who put their names & birth/death dates on the front side of the bowl and then she dug a shallow ditch (so to speak) to imbed the bowls partially into the ground. Each spring she planted pretty flowers in the bowls.