A quick solution:
select cast(cast(datepart(month, dateadd(month,1,getdate())) as varchar(2)) + '/1/' + cast(datepart(year, dateadd(month, 1, getdate())) as varchar(4)) as datetime)
Note: It's important that the new date (i.e. dateadd(month, 1, getdate()) is used for the year portion since...