Israel has 4 cellular networks: Orange, Cellcom, Pelephone and Mirs (all links in Hebrew). The first two are more popular and are considered larger than the last two.
In Israel, most cellular phones are marketed by the cellular operator, and therefore, the popularity of a specific model or manufacturer is very much dependent on the cellular operator who markets it. Orange and Cellcom, which as I said are considered to be the two largest operators, mainly (but not exclusively) promote phones by Nokia and Sony-Ericsson, though you can also find Motorola and Samsung phones used in their networks. Pelephone and Mirs promote mainly (but not exclusively) Motorola's phones, but you can find also phones by LG.
Therefore, it is safe to assume that Nokia and Sony-Ericsson are the two most popular cellular phones manufacturers in Israel.