Wait... We Have A Yard???

So, if you know me very well, you know I've wanted a house for a while. I'm a planner and this means that while I dreamed of owning a house some day I spent my time planning what I would do with a house. I thought of color schemes, architectural feature to look for when house hunting, even looked at furniture ahead of time. All of this means that now that we own a house I'm in 'get it done' mode. I didn't need to shop for a couch, because I knew I wanted the ikea one. I didn't have think about the pros and cons of laminate flooring because I had already considered them. LJ pretty much just asks me "what's you're plan for XXX" instead of "what should we do about XXX". But in all my planning, there is something I never really thought about...our yard.

I'd like to play it off like I didn't bother worrying about our yard because I didn't know how big it would be. While this is valid, it's not really the reason. I didn't worry about it because it doesn't interest me terribly. I like pretty yards, but I've never thought about what it takes to go from ugly to pretty. I haven't really researched anything either. This lead to the look of total shock I got from LJ when he asked "what's your plan for fixing the backyard?" and I just shrugged. 

See, the foundation guys had to dig up the back half of our backyard in order to connect our pipes to the sewer system. I totally don't know what's normal so I don't know if this is a usual problem when you get your pipes replaced or if we're just 'lucky'. All I know is that it's left our yard looking like this:

Here's a close up of just the back half. As you can see, it's composed of giant clumps of clay like dirt:

Any idea what we do? The clumpy dirt is way higher than the ground with grass is (the lawn guy comes today for the first time, soon it wont look so jungle like). So, even if we were to just sprinkle it with grass seeds our yard would be completely uneven. People have suggest a rake, which we tried and it didn't do much. Any ideas? Seriously folks, if you know something we don't, please share...

I've also got this weird group of plants in the space between the garage and the fence. Not sure what to do with it, but I really like the purple flowers, so they'll stay.

Oh, and our driveway has it's own lawn...aka the grass is growing in the cracks. I'm pretty sure we have to poison this sometime soon so it doesn't cause damage...right?

See, we're complete noobs here... fixing a house is complicated enough, now we have to figure out what to do with this thing they call a yard... Help!!!