Famous from Boardwalk Empire, Mad Men and other historical dramas, the club collar is probably due for a revival. With rounded tabs, it looks like this:
Club collars should be short (less than two inches), and the distance between the tabs (width) should be about the same as the length of the tabs. In other words, you don’t want one too spread out, and if the tabs are too short they will not fold over your tie.
As with the spearpoint, the club collar can take a collar bar or pin, and some are made with an attached tab that you can button under your tie. This, from the great Soshei Yamazaki’s 30s Style website, is probably the ultimate in club collars, and Soshei has a great collection of vintage collar pins and bars.
Finding club collar shirts is a lot easier than finding spearpoint collars. If possible, of course, have them made MTM to ensure that they are the right size for you, and to avoid a big spread at the top, over your tie. The two sides of the collar should meet at the top, so you will need a smallish knot. In addition, with MTM you can ask for two small holes for the collar bar.