ник: snipe
может так (хотя не уверен)
SELECT t.nomertel AS Выражение1, (select sum ( r.summazvonka) as wer
from Tabl as r where r.nomertel=t.nomertel) AS сумма
FROM [SELECT s.nomertel
FROM Tabl as s
where s.opisanie like '*рег*']. AS t
GROUP BY t.nomertel
HAVING ((((select sum ( r.summazvonka) as wer
from Tabl as r where r.nomertel=t.nomertel))<>0))