It's quite easy in FileMaker, but can be quite different than how you do it in Access, so you have to unlearn a few old things at the same time you learn how filemaker does this.
Are you sure you need this at all in your FileMaker file?
In FileMaker, you can:
1) Enter find mode
2) type text such as the first letters of a name into a text field
3) perform the find
All without any development work by us developers.
If you want your selection box, take a look at this demo file. The two portals at the bottom of the layout act much like what you describe here. And yes, you can relate a table to itself in a "selfjoin" to set up such a portal if you want to. You just need to create an extra table occurrence of the same table in Manage | Database | Relationships.
Thanks, Phil. I will evaluate this example. You are probably right, I'm trying to do things "just like Access". I appreciate the comment.