As Leni as said, those of us outside the USA will probably have little knowledge of weights like your Joe St Clair example.
But I can answer Leni's question about whether St Clair weights are signed or identified in any way. They always (?) have an impressed mark on the base, which can just about be seen in the base image that has been shown. For weights from the St Clair family, the name "St Clair" will be shown along with the first names, the most common being "Joe" and "Bob & Maude".
(Also, in the St Clair line is Joe Rice who makes very similar weights.)
I can also say that the design of this weight is known as a "Calla Lily" and this has been a very regular theme in weights from various American makers for many years.
Various St Clair examples can be seen quite regularly on eBay and this may be a good way to determine the current selling price. There are at least 38 St Clair paperweight items listed (picked up through the UK version of eBay) as I write this.
For the weight marked with a "G" and "Glasshouse", I have no knowledge of this. But, as with all the other weights, Marilee, please do post pictures as this will be helpful to me, at least, as well as possibly getting you some assistance.