Linked lists, pointers and nodes

I'm trying to further my understanding on Linked lists, nodes and pointers. I've written some code, received some compiling errors that I'm not sure how to fix and was hoping to get some direction here. Below is my code + compile errors at the bottom.

#include <stdlib.h>
#include <stdio.h>

typedef struct _node 
{
    int data;
    struct _node * next;
} node_t;

typedef struct 
{
    node_t * head;
    node_t * tail;  
} LL_t;

unsigned int removeNumber(LL_t * L, int target);

LL_t * LLcreate() {
    LL_t * ret = malloc(sizeof(LL_t));
    if (ret != NULL) {
        ret->head = NULL;
        ret->tail = NULL;
        }
    return ret;
}

// Adds a new element to the tail end of a list
void LLappend(LL_t * LL, int value) {
    node_t * newNode = malloc(sizeof(node_t));
    if (newNode != NULL) {
        newNode->data = value;
        LLappendNode(LL, newNode);
    }
}

void LLappendNode(LL_t * LL, node_t * newNode) {
    if (newNode != NULL) {
        newNode->next = NULL;
        if (LL->tail == NULL) {
            // empty list
            assert(LL->head == NULL);
            LL->head = newNode;
            LL->tail = newNode;
        } else {
            // non empty list
            LL->tail->next = newNode; // seg fault
            LL->tail = newNode;
        }
    }
}



// Post: removes data target from list L
unsigned int removeNumber(LL_t * LL, int target) {
int count=1;
node_t * curr = LL->head;

while(LL->head && LL->head->data == target){
    node_t * temp= LL->head;
    LL->head=LL->head->next;
    free(temp);
    count=0;
    }

while (curr->next!=NULL){
    node_t * temp = curr->next; 
    if (curr->next->data == target){
        curr->next = temp->next;
        curr=curr->next;
        free(temp); 
        count=0;
        return count;
        }
    }
}

int main(){
    int LL[6]={1,2,5,3,4,6};
    int i;
    LLcreate();
    for (i=0; i<10; i++)
        {
            LLappend(LL_t * LL, i);
        }
    for (i=0; i<10;i++)
        {
            printf("%d", LL[i]);
        }

}

Compiling errors

splcie.c:36:6: warning: conflicting types for 'LLappendNode' [enabled by default]
 void LLappendNode(LL_t * LL, node_t * newNode) {
      ^
splcie.c:32:9: note: previous implicit declaration of 'LLappendNode' was here
         LLappendNode(LL, newNode);
         ^
splcie.c: In function 'main':
splcie.c:84:22: error: expected expression before 'LL_t'
             LLappend(LL_t * LL, i);
                      ^
splcie.c:84:22: error: too few arguments to function 'LLappend'
splcie.c:28:6: note: declared here
 void LLappend(LL_t * LL, int value) {
      ^