How do I shoot photos that crop well into a very wide website hero banner?

Without seeing some examples of what you tried, without success, to capture it is difficult to understand exactly why you are wanting to display and why you are unhappy with the results. I'm guessing it is one of two issues that are thwarting you: resolution or composition

• Resolution. The limiting factor here isn't about how wide is the lens used. The limiting factor is how much detail you can include in a 1005x300 px image. You can use longer focal lengths to produce a wide panorama of a scene such as your company building, but when you reduce it to 1005x300 px you throw away all of the detail you gained by stitching together multiple images.

• Composition Most subjects are difficult to pull off in an image that is over three times as wide as it is tall. This is particularly true of people, since most of us are much taller than we are wide. Even a head shot that displays only a face needs a space relatively square for it to look right, and usually even there the slightly longer side is the vertical, not the horizontal one. An 8x10 portrait has a 1:1.25 ratio favoring the vertical dimension. It is virtually impossible to fit a single person into a horizontal image with a 1:3 ratio (unless they are reclined, but I doubt boudoir is what you are after). The usual solution is to place them as a relatively small element in an environment that lends itself to horizontal composition: either a landscape or an architectural setting that is primarily horizontal. That is what your example has done with the bride and groom: placed them in a horizontal landscape. The problem when you do this is that it is difficult to convey more about the people in the photo than the environment they are contained in. Your sample is rescued by the almost universal recognition that the female subject is wearing a wedding dress, the male is dressed formally enough, and the couple is in an intimate position so that the viewer draws the conclusion this is a bride and groom. But the image tells us nothing about who this bride/groom are and what is unique about them: the viewer is left at that point to fill in the blanks from their own experience. And even then the composition doesn't work because the rocks on the left are in sharper focus than the couple whose feet have been cut off to fit the artificial horizon where the field meets the trees into the scene and leave a lot of open dead space in the middle for the text.

You need to decide what you want to use the space to communicate: either the content of the text with a "background" image that doesn't detract from the text or visual information communicating what your organization represents or who you are. A possible compromise would be to offset the text to one side and place the visual focus of your image on the other (but closer to the center, rather than the bottom, of the right edge): perhaps the couple properly focused and standing in the area behind the groom's right shoulder.