Can you use Strike and Run, or Call for Friends type attacks to retrieve Fossils from your deck? What about using Pokémon Retriever to get them from your discard pile?
No, you cannot search for a Fossil trainer with any Pokémon searching technique.
Source: PUI Rules Team (2005-07-07)

Relevant cards

Note: All applicable cards may not be listed below.
DP1_55
DP7_79
PL4_59