Google Sheets Script

function fetchData() {
  var sheet = SpreadsheetApp.getActive();

  // Get the user inputed data
  var inputSheet = sheet.getSheetByName('Inputs');
  var apiKey = inputSheet.getRange(1,2).getValue();
  var region = inputSheet.getRange(2,2).getValue();
  var realm = inputSheet.getRange(3,2).getValue();


  // Assemble the URL and fetch the csv file
  var csvUrl = Utilities.formatString("http://api.tradeskillmaster.com/v1/item/%s/%s?format=csv&apiKey=%s&fields=Id,Name,MinBuyout,MarketValue", region, realm, apiKey);
  var csvContent = UrlFetchApp.fetch(csvUrl);
  var csvFile = csvContent.getBlob().getDataAsString();

  var csvData = CSVToArray(csvFile);// convert to 2D array

  // Clear all the data and then rewrite new stuff
  var dataSheet = sheet.getSheetByName('Data');
  range = dataSheet.getRange(4, 2, csvData.length, csvData[0].length);
  range.clearContent();
  range.setValues(csvData);
  SpreadsheetApp.flush();
}


function CSVToArray(strData){
  var rows = strData.split("\n");
  var array = [];
  for(n=0;n<rows.length;++n){
    if(rows[n].split(',').length>1){
      array.push(rows[n].split(','));
    }
  }
  return array;
}