>I have invested in a good Manifrotto tripod and ballhead and >remote.
That's good. I'd suggest you fill in the equipment section of your profile so we don't have to guess at what you're working with.
>Since landscape doesn't require higher ISOs or fast >lenses, it comes down to what wide angle lens will produce the >sharpest picture from edge to edge, right? Any suggestions >along those lines?
Luckily for landscapes you're shooting at small-ish apertures (f/8-f/16) which tends to equalize issues with lens performance, so you don't really need best-of-the-best to get excellent results. The question of which ultra-wide will be tied to your question of FX or DX.
On the DX side I consider the Nikkor 10-24 to be the best option, but there are some excellent choices sub-$500 like the Sigma 10-20 or Tokina 12-24.
On FX I think the most reasonable choices boil down to Nikkor 16-35 f/4 vs. Tokina 17-35 f/4.
>Even though I travel a lot, living in Lancaster County, PA we >have a lot of scenic views right here at home.
Indeed that's ideal, no matter where you are, to appreciate what's around you every day. It helps to be in a nice area too
>P.S. I love your Pigeon Point Lighthouse HDR photo. It's >magical.