When I was hosting my dh's 30th b-day party, I was fortunate enough to stand next to an old Italian couple while in line at the butcher. They very frankly and correctly told me I was making it harder than I needed to. We were having 80 people! They SAVED me and I'm so glad I listened to them. Here's what they told me and what I did.
you can bake Italian sausage, a single layer in a pan with sides, for 20 mins per side at 350 degrees. be sure to pierce them first for obvious, painful reasons.
Take a large top or bottom round roast and seer both sides then put it in the bottom of a large crock pot. Top it with a jar of giardinaire and cook on low for 6-8 hours - it makes EXCELLENT Italian beef. (my dh's stepmom makes this for family things now, apparently she really liked it that day)
On the stove, sautee bell peppers with olive oil & garlic. They go great with the other stuff.
Serve these with good Italian bread cut into decent sandwich sizes & cut with slits so they are easily opened. Serve buffet style so they can help themselves. Add some good spaghetti sauce for people who want it with their sausages and that's even better. I like to put out good grated parmesan cheese, and slices of provolone, too.
I also added an easy dish - another crock pot thing so it's easy, breazy. Get good frozen meatballs & a good spaghetti sauce, put them into the crock pot & cook on low 3 hours, will keep most of the evening so you can leave it for people to help themselves.
Lasagna is great, too. Easy because you can make it the day before and bake before the party. You can make spinach lasagna for people who don't eat meat, to balance all the other stuff I mentioned. There's a great recipe in the better homes & gardens cook book, or check their site. It's great, I've made it a million times with great fanfare. My mil even requests I make it sometimes for family gatherings.
People offered to bring dishes so I let them. We ended up with broccoli salad; tomatoes with fresh mozzarella or feta with balsalmic vinegar & Italian seasonings and fresh basil; potato salad, egg salad, a nice green salad; and other things I can't remember 7 years later lol. But it worked really well and I stayed sane despite having 80+ people in my house!
I've hosted plenty of parties since then and find that people generally offer to bring something so have a list of what you want to serve and when people ask if they can bring something, go down your list unless you know a)they can't cook (in which case you say a bottle of red would be great!) or b) they have a specialty they might bring.
Last summer we had a graduation/going away party for my son who was headed to the Air Force. We had a pig roast. I had my list and everyone offered food so my mil's famous beans were very necessary. After that I did like I mentioned before and well I didn't cook ANYTHING! I had plenty other stuff to do, but there was a moment when the pig was off the spit & being carved but not everyone else was there so I thought boy we'll be pork & beaners here but heck we had a keg to wash it down so bring it on! lol. Well the last minute everyone came and poof, we had an EXCELLENT buffet set up in the kitchen for people to walk through and peruse.
For a huge group (this time more than 150!) buffet style is the only way to serve! And heck with live music they were all set. What could anyone complain about?! What would they do, demand their money back? lol.
Have fun!
D.