Looks like json to me, so you could extract it by using this here:
$value = file_get_contents('http://steamcommunity.com/market/priceoverview/?country=US¤cy=3&appid=730&market_hash_name=StatTrak%E2%84%A2%20P250%20%7C%20 Steel%20Disruption%20%28Factory%20New%29');
$json = json_decode($value);
$variable = $json->lowest_price;
echo $variable;
So you might look also at this: http://www.w3schools.com/json/
2
solved Request a Steam marketprice item lowest value