The erliest and most basic are the tsearch(), bsearch(), lsearch(), hsearch(), qsort() family:
Man Page for tsearch (linux Section 3) - The UNIX and Linux Forums
C++ Standard Template libs has many very basic containers (no hash):
STL Containers - C++ Reference
map - C++ Reference
To get the hash, many of my employers have had roguewave h++ libraries:
RWTPtrHashTable<T>
Don't overlook the fine container objects in JAVA, like tree map:
TreeMap (Java Platform SE 6)
Google reveals a myriad of open source containers/lists/maps/trees/tables. Some RDBMS implement a multi-column index as containers of containers of containers, so each column can be looked up even if others are not there (so the whole container is iterated). Many good wiki on the high level concepts of hash and such, very good to know first, so API controls make sense.
Finally, awk and bash have associative arrays or lookup vectors, which are hash maps (learn the lingo or get out). Just be careful you are not in the simple "array addressed by integer" tutorial! I am sure PERL has all this, too, so read the wiki and pick your poison. Do you grasp the array, linked list (sorted and unsorted), tree and hash basic concepts?