Irgend is used to reinforce uncertainty similar to some/any.
Examples
Hat irgendwer meine Tasche gesehen?
Has anyone seen my bag?
Kannst du es irgendwo sehen?
Can you see it anywhere?
Sie suchen irgendwas.
They're looking for something.
Regarding the differences you're interested in:
irgendwas and etwas are synonyms. like the example above could also be written as:
Sie suchen etwas.
Irgendeine and einige however are quite different. Einige is used for small groups.
Example:
Es gibt einige mögliche Übersetzungen.
There are several possible translations.
Irgendeine, as said at the beginning, just expresses uncertainty.
Example:
Gibt es irgendeine Lösung?
Is there any solution?