There we have a slight problem, I'm only going on a spoken name Aberdroth (Don't Know correct spelling) can't find on a map, or on anything else. The farm was located between Llangurig and Llanidloes which is Montgomeryshire. Thats why I was hoping to find a site where I could search area's. Had a look on the historical directories and not had any success there.... driving me nuts!!!!
The hard way to do this is to search through the census images page by page on a site like ancestry or findmypast.
To do this on Ancestry, I go to search but don't put any names in. Look for UK Census Collections and then the year. then the county (montgomeryshire, in this case), then the civil parish (Llanidloes or Llanidloes Without), then go through each enumeration district. On Ancestry, there is also the front page of enumeration district, which is the enumerator's description of the district.
So, District 5 of Llanidloes Without (picked at random) is described as bounded "On the north, the middle of the Bryndn Road, on the East the wood known as Llellcockynaus and Old Quary Bryncach Wood & Byrndn, on the South Brynpaskg Hill" (sorry for the appalling attempt at transcription of the Welsh placenames).
Then you get a description of the enumeration district: "Part of the Parish of Llanidloes, from Maenol Dulas Villa ..." I'll not risk the further ire of the Welsh by trying to transcribe anymore.
These descriptions exist for each of the enumeration districts for the civil parish, so you may be able to find the appropriate one(s) by reading the descriptions, rather than ploughing through the census pages one by one.
Of course, there's the risk that the name you know it by, might not have been the one used then.
Presumably you're looking at the building/farm's history, rather than the individuals who lived there (otherwise why can't you look by name?).
Two other suggestions:
1) Try asking on the
Montgomeryshire board here on rootschat
2) Try a search for the property name on Access2Archives and/or the Powys Records Office. A farm is likely to have changed hands several times over the centuries, and they may copies of documents relating to the sale/bequest of the farm.