Some comments

"Feminine nouns such as Hrvatska (in its nominative form) will have an -e replacing the -a on the end of the noun, so Hrvatska in its genitive form is Hrvatske."

This is VERY misleading, since Hrvatska is NOT a normal feminine noun, but changes as an adjective: gen. Hrvatskoj.

"The dative also is used in prepositions such as u (in), na (on), pod (under), pred (in front of) and kroz (through)"

This is actually the locative case after u, na, o. But it's forms are the same as the dative, something that has to be mentioned.

"The accusative is the object of a sentence. From the earlier sentence, I was going home, I was the nominative, and home is the accusative. Masculine and feminine nouns in the singular accusative endings depend if the object is moving. If the object is inanimate like a town or house, the word doesn't change, it stays as the accusative, but if the object is moving, it will be the same as the genitive, like say that the town was moving, for some strange reason."

This is simply false. Accusative of masculine inanimate nouns is same as nominative, and of masculine animate nouns same as genitive. This has nothing to do with the feminine nouns. Also, has nothing to do with the motion.

The motion has to do something with prepositions u, na, which must use accusative if it means motion (the same as in German).

"The locative is used to denote certain locations, such as:"

It's used with some prepositions denoting locations, but not with all of them. "ispod stola" uses gen. and it's a location. "pod stolom" uses ins. and it's a location, etc.

"The masculine nouns end with -u when in the locative, and feminine nouns end with -i when in the locative. The main prepositions followed by the locative are "in" and "on"."

Neuter nouns are not mentioned, and neither i-class of nouns...

"The instrumental is used to denote actions, such as:"

Not actions, but means of doing actions or any tools used. And it's used with prepositions s, pod, nad...

"Below are a few examples of some nouns and how they change with what case, whether they're masculine, feminine, singular or plural. It is very hard to remember the cases and how nouns follow, so this will help to have a clearer picture of it all."

It fails to mention that cases are much simpler in plural, also pattern for i-nouns like "stvar" is not given.

"Nouns that have -k as the last letter change to -c before going into the cases."

This is again incorrect. k, g, h changes to c, z, s only before -i- in case endings:

putnik, putniku (dat.), putnika (acc.), putnici (nom. pl.) putnika (gen. pl.) putnicima (dat., loc., ins. pl.)

"Locative is only when we have preposition about. Eg. 'About school' translated to Croatian 'O školi'. This is locative. And with in can be only accusative or dative eg. I'm at school. - Ja sam u školi. - dative; I'm going to school. - Idem u školu. - accusative"

And even this rule doesn't work always for dative sg. of feminine nouns.

This page needs a lot of work.