How many albums has the band silverstein made?

It depends on if you're talking about official albums or if you want to include promotional releases. Official releases are as follows:

Fragile (as Saron Gas) (2000)

Disclaimer (2002)

Disclaimer II (2004)

Karma and Effect (2005)

One Cold Night (2006)

Finding Beauty In Negative Spaces (2007)

Holding Onto Strings Better Left To Fray (2011)

visit Seether-Online to view the full list of promo releases

source: seether-online.com/discography