Weddingbee boards

So my caterer became a tad bit uncooperative when we said we wanted to handle linens and plates etc ourselves. We were absolutely willing to work with them, but the rental company they use just did not have what we were looking for. Sooo...we're planning on buying overlays, napkins and all flatware/dinnerware ourselves. I was hoping there was an expert/experienced bride running around to give me an advice on what we need to estimate.  

Guest list? ~170. About half the list is from out of town. I'm guessing maybe 100 will show up?

Guest tables: 60" rounds. We plan to sit 8 at each.

Banquet tables: 8'. I imagine these will be used for food and dessert.

We're getting the awesome Bambu Veneerware stuff for plates/flatware. There are 11", 9", and 7"plates. We were thinking 11" for lunch and 7" for dessert. I was thinking 2 forks, 2 spoons, and 1 knife per person. How many of each item do you think we should be order to be on the safe side?

We're having a casual lunchtime wedding. The food will be buffet style. We are having a dessert buffet. Any idea how many 8' tables the caterer is likely to need for a buffet and dessert?

Does anyone who did their own linens/tableware have any other advice?

Thanks for any help!